Architects or carpenters. Both are essential to building a structure but their roles could not be more dissimilar. And confusing the two could lead to a disaster. It’s best to be clear about which one you want. Because if you have the vision and really all you need is someone to put it together, you’re going to lose a lot (credibility, good will, regard) by hiring someone who excels at the design (or, worse, to convince someone that you want them for the building but really want them for the design…or vice versa). It’s okay want one or the other, but make it transparent.